

586 

WWUS20 KWNS 161942

SEL5

SPC WW 161942

OKZ000-TXZ000-170300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 155

NWS STORM PREDICTION CENTER NORMAN OK

240 PM CDT THU APR 16 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       OKLAHOMA PANHANDLE

       WEST TEXAS INCLUDING THE PANHANDLE



EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 240 PM UNTIL

1000 PM CDT.



HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 80

STATUTE MILES EAST AND WEST OF A LINE FROM 20 MILES NORTH OF

GUYMON OKLAHOMA TO 50 MILES SOUTH SOUTHEAST OF LUBBOCK TEXAS.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU5).



REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE

FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH

AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR

THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS

AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY

DO PRODUCE TORNADOES.



DISCUSSION...THUNDERSTORMS WILL CONTINUE TO INCREASE IN COVERAGE AND

INTENSITY THIS AFTERNOON AND EARLY EVENING AS SHORTWAVE TROUGH OVER

NM APPROACHES REGION.  STEEP MID LEVEL LAPSE RATES...MODERATE MUCAPE

VALUES...AND FAVORABLE EFFECTIVE SHEAR SUGGEST A RISK OF SUPERCELLS

CAPABLE OF LARGE HAIL AND DAMAGING WINDS.  POTENTIAL FOR ISOLATED

TORNADOES COULD ALSO INCREASE THIS EVENING WHEN AN UPGRADE TO A

TORNADO WATCH MIGHT NEED TO BE CONSIDERED.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM

MOTION VECTOR 24035.





...HART

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